Grooved fasteners, such as grooved nails are known. Shelton, U.S. Pat. No. 7,845,889, discloses a fastener having a shank having a plurality of longitudinal grooves to reduce the amount of material needed to create the nail and increase the holding power of the nail, while only minimally affecting the bending yield strength of the nail and other important properties of the nail.
Such a nail includes a relatively large number of relatively shallow grooves disposed about the circumference of the shank. Formation of the grooves does not alter the geometry of the shank such that the nail can have a full round head. Such grooved fasteners may also include a ring shank (e.g., a ring shank nail) in which circumferential rings are formed in the fastener to further increase the holding power of the fastener.
Grooved fasteners work well for their intended purpose. However, fasteners such as nails formed from common steel typically require a coating or plating of some type to prevent corrosion. One commonly used coating or plating is a zinc coating applied in a galvanizing process. Galvanizing provides a corrosion-resistant coating on the underlying fastener and also serves as a sacrificial anode in the event the coating is scratched away from the underlying material.
One drawback to galvanizing the nails is that, especially with smaller gauge nails, the zinc will plate the surfaces that define the grooves and the spaces between the rings in a ring shank nail. This can tend to reduce the holding power of the nails.
Accordingly, there is a need for a plated spline fastener or grooved fastener that includes a corrosion resistant coating and a method for making same. Desirably, such a coating is applied so as to minimally, if at all, negatively affect the holding power of the fastener. More desirably still, such a coating is applied so as to not overcoat the surfaces that define the grooves and so as to not “fill” the spaces between the rings of a ring shank nail.